The users of motor vehicles have differences in height. The possibilities of adjustment of the driver's seat are adapted to the operating elements, such as the steering wheel and the pedals. In the event of the holding device used so far, which allows only an inclination of the interior mirror, the height of the interior mirror thus represents a compromise, which is oriented on the "average height" of the drivers.
For small drivers the interior mirror is, therefore, fitted too high. In order to observe the traffic behind the vehicle, it is under these circumstances necessary to raise one's head in order to look into the interior mirror, something drivers of an average height can do by merely raising their eyes. As a result attention is deviated for a dangerously long time from the traffic in front of the moving vehicle. In some instances it is not even possible to observe the traffic behind the vehicle by means of the interior mirror, since in order to be able to look into the mirror, it must be inclined to such an extent that it is no longer directed to the rear window of the vehicle, but to hat rack and/or the trunk lid.
For tall drivers the interior mirror is fitted too low, so that it restricts part of the field of vision on the right at the front. This results in dangerous situations, because other vehicles or pedestrians are masked by the interior mirror when turning right and the course of right turns can sometimes not be seen without moving the entire upper part of the body in order to look past the interior mirror.
It is, therefore, appropriate to install the interior mirror in vehicles in such a way that its height can be adjusted.
Several proposals have been made in the prior art with respect to the design of such a holding device, such as a telescopic arm as described in German Patent No. DE 35 46 344 A1, published Jun. 12, 1986, or a second joint at the foot of the holding device as described, for example, in the German Patent No. DE 33 36 795 A1, published May 2, 1985, and German Utility Model No. G 83 18 309.4, published Oct. 20, 1983 or devices with two mobile arms as described in German Patent No. DE 33 37 745 A1, published Apr. 25, 1985, or a device which consists of a parallelogram, as described in German Utility Model No. G 80 22 080.0, published Jun. 11, 1981.
A common feature of all of these prior art proposals is that the entire holding device can already be misadjusted through the normal adjustment of the inclination of the interior mirror or during dimming, so that both hands must frequently be used for such simple handling procedures. Because of the many joints there is a risk that the entire holding device becomes unstable after a prolonged service life and the interior mirror is misadjusted during driving, for example, by vibrations.